Environmental issues

On November 18, 2007 Colombian newspaper El Tiempo reported that the river was receiving an average of 500 tons of residual waters a day. Pollution from the city of Popayan, seven gold mines that also add industrial pollutants such as mercury, some 8 sand mills, plus a couple of mines of coal and bauxite. Cali, the largest city over the river depends on the river in a 76%. Adding to these other affluent rivers collect residual waters from other major cities and deposit an aproximate of 330 tons of residual waste into the river, by the time it gets to Yumbo the river has no oxygen.